U-flow flap slitter

ABSTRACT

UNIT, THE FLAP CONNECTIONS ARE SEVERED AND THE UNDERLYING FLAPS ARE FOLDED TOWARD CLOSED POSITION. A MECHANISM FOR SEVERING THE STRIP CONNECTIONS BETWEEN THE EDGES OF DOWNTURNED CLOSURE FLAPS HELD ALONG THE OUTER SURFACES OF THE VERTICAL WALLS OF A PAPERBOARD CASE AS IT IS ADVANCED ALONG A CONVEYING MEANS FORMED AS A U-SHAPED UNIT TO ADAPT THE UNIT TO FIT BETWEEN ALIGNED CONVEYOR SECTIONS. AS THE CASE ADVANCES ON THE

Feb 2, 1971 w. E. STANDLEY ETAL 3,559,368

U-FLOW FLAP SLIITER Filed Nov. 12; 1968 1 w. fimww m y r 6 W @X 2 m [MM 54 m? Feb. 2, 1971 w s'T Y ET AL U-FLOW FLAP SLITTER 2 Sheets-Sheet 2 .Filed Nov. 12, 1968 United States Patent fiffice 3,559,368 U-FLOW FLAP SLITTER Wendell E. Standley, Lake Forest, and Lamar W. Sorensen, Des Plaines, lll., assignors t Johns-Nigrelli-Johns, Inc., Skokie, 111., a corporation of Illinois Filed Nov. 12, 1968, Ser. No. 774,897 Int. Cl. B65b 11/20, 61/00 US. Cl. 53-167 13 Claims ABSTRACT OF THE DISCLOSURE The present invention is related to and in certain respects is an improvement over the mechanism disclosed in copending applications, Ser. No. 478,371, filed Aug. 9, 1965, now US. Pat. 3,373,543, and Ser. No. 660,665, filed Aug. 15, 1967.

The advantage in employing paperboard cases in which the cover flaps are held in downturned positions by connecting strips in close relation to the vertical walls of the case is that the flaps, being so held, facilitate the case loading Operation. If the flaps are not held close to their attached walls as the case advances it is usually desirable to control them with guide rails to assure that they will not interfere with the loading operation.

After the cases are filled, the connecting strips between the flaps must of course be severed before the flaps can be folded into closed position and sealed. In certain operations, the cases, after being filled, are conveyed from the loading station to the gluing and sealing station on a straight line conveyor of some length; and it is feasible in certain instances to modify this conveyor by forming a break at a median point and introducing the U-flow flap slitter of the present invention. During the time the cases are diverted onto this mechanism the connecting strips are severed to release the flaps and the underlying flaps are folded substantially to closed position preparatory to the delivery of the case to the flap sealing station.

An important object of the present invention is to pro vide a unitary mechanism for severing flap connecting strips that can be readily incorporated into a case conveyor line at an intermediate point between the case loading and flap sealing stations, and in addition to severing the flap connections, advantage is taken of the U-flow arrangement, whereby the underlying flaps may be folded by means of plow bars to positions in which they are in a small angular relation to the top of the case before the case is returned to the main conveyor line.

Other and more specific objects and advantages of the present invention will become apparent as the description proceeds.

In the drawings, FIG. 1 is a somewhat diagrammatic plan view of a U-flow unit on which case flap connections may be slit or severed, this unit being shown operatively connected with sections of a main conveyor line;

FIG. 2 is a perspective view of the form of paperboard case having downfolded, connected flaps, the connections of which are designed to be severed on the unit illustrated;

FIG. 3 is a fragmentary plan view, similar to FIG. 1, showing a connection cutting blade located in the transverse, or closed, section of the U-flow unit instead of being located on the second leg of the unit;

3,559,368 Patented Feb. 2., 1971 FIG. 4 is a diagrammatic vertical sectional view taken on line 44 of FIG. 1 showing the transverse guide member Whlch swings the folded flaps an additional distance after they have been folded by the plow bars on the second leg of the U-fiow unit; and

FIG. 5 is a vertical sectional view taken along line 5-5 of FIG. 4.

Loaded cases with their cover flaps held along their vertical walls are delivered onto the conveyor supporting surface at the end of one leg of the U-shaped unit. The case is stopped in position so that it may be advanced at a right angle along the first leg of the U and past a suitable severing means, such as an upwardly extending blade, which will sever the first flap connection. The case continues to be advanced to the closed or transverse end of the unit where it is again stopped. The case is next advanced along the transverse end of the unit where the second flap connection is severed. Following this, the case is advanced along the second leg of the unit. If desired, the cutting blade may be located on this section instead of the transverse section of the unit. Flap folding plows are arranged along the second leg to fold the lateral flaps as the case advances. These lateral flaps are folded or swung over and downward to a small angle relatively to the top of the case before the case reaches the limit of its movement. The flaps are then brought into contact with a guide member, arranged transversely of the case path, which swings the flaps still farther downward toward their closed position as the case comes to a stop. The case is thus brought back into alignment with the main conveyor and may then be transferred thereto. As the case moves onto the main conveyor the lateral edges of the downfolded flaps continue in contact with the transversely positioned guide member to maintain them in lowered position. The particular function of the trans verse guide member is to hold the flap that has become the trailing flap in its lowered position until it has moved out from beneath the plow bar which has folded the opposite flap, which has then become the leading flap.

Referirng more particularly to the drawings, a typical form of case on which the unit is designed to operate is indicated as a whole at 1. The sections of the main conveyor line within which the U-flow unit is incorporated are indicated as a whole at 2 and 3.

The flow units shown in FIGS. 1 and 3 are indicated as a whole at 4A and 4B. The units are generally similar except that, in unit 4A, the two strip cutting blades are located in the opposite legs of the unit, while in unit 4B the second strip cutting blade is in the transverse section of the unit.

The case 1 may be formed from a single blank of paperboard secured at the box factory in collapsed tubular form. It comprises four interconnected end and side walls 10, 11, 12 and 13. Cover flaps 14, 15, 16 and 17 are hinged respectively to walls 10, 11, 12 and 13-. As shown, cover flaps 14 and 15 are integrally joined by short strip 18, and flaps 16 and 17 are joined at the diagonally opposite corners of the case by strip 19. Before expanding the collapsed case aligned flaps 14 and 15 and the opposite aligned flaps 16 and 17 are folded so that they will lie flat against their attached walls. The case is then expanded and the bottom flaps secured in place as shown. The connected flaps will be retained in close relation to their attached walls. It is to be noted that the free vertical edges of flaps 15 and 16 will normally flare somewhat outward at one corner of the case, and the free vertical edges of flaps 14 and 17 will flare outward at the opposite corner. The vertical dimension of the flaps in the positions shown is such that their lower edges terminate above the lower edges of their attached walls.

While not illustrated, it is to be understood that when the cases are to be treated by the mechanism herein shown they have previously been loaded and are ready to be closed and sealed after the cover flaps have been released by cutting the connecting strips 18 and 19.

The loaded cases are carried lengthwise on conveyor section 2, with end wall 12 leading and end wall trailing. Suitable control means, forming no part of the invention, will be employed to feed cases in spaced relation on conveyor section 2. If desired, the spacing of the cases can be controlled manually.

Cases delivered from the end of conveyor section 2 are received on a plurality of relatively long live rolls 21, 21 rotating in a surface direction to continue the advance of the case until the case has moved completely onto the rolls. The series of live rolls 21, 21 comprises a conveyor support means which forms the first leg of the U-flow unit. The closed, or transverse, end of the unit is formed by a series of additional live rolls 22, 22 of shoter length, and the second leg of the U-flow unit is formed with a plurality of rolls 23, 23 of a length comparable with the long rols 21, 21. The rolls are mounted for rotation on suitable spindles the ends of which are received in openings formed in frame members. The principal side frame members are indicated at 24 and 25 which support the ends of the long rolls. End frame members are indicated at 26 and 27. The short rolls 22, 22 are supported at one end by the side frame member 25 and at the other end by intermediate frame member 28 which is joined to a transverse frame member 29 at the side of the first leg of the U-fiow unit. The frame members illustrated are supported on a suitable base frame, not shown.

While the machine is in operation the rolls are constantly driven by suitable drive means, such as the roll drive mechanism disclosed in the above mentioned pending applications.

After the case has moved onto the rolls 21 it is brought to a stop by a guide rail 31 supported on frame member 29. This guide rail is low enough so that it will be contacted only by the lower edge portion of the leading wall 12. The unsecured, outwardly flaring end of flap 16 hinged to end wall 12 will not engage the rail 31 and will extend beyond the outside edge of the rail. While the case is urged against the rail 31 the rolls 21 rotate harmlessly beneath the case.

For the purpose of cutting the strip 19 joining end flap 16 and side flap 17 an upstanding blade, indicated at 32 is supported in line with guide rail 31 at a point spaced from the case path as the case moves into contact with the rail 31. The height of the blade is sufficient to enable it to be contacted by the strip 19 when the case is ad vanced past the blade. The particular arrangement of the guide rail and fixed cutting blade has been disclosed in detail in the applications referred to above.

The means herein shown for propelling the case along the guide rail 31 and past the cutting blade 32 comprises a follower plate 33 fixed on the end of piston rod 34 actuated by a piston in cylinder 35. The follower plate will be in its retracted position when the case is moved onto the rolls 21; and, after the case has moved against the guide rail 31, the piston rod is actuated to move the case past the blade and thence onto the end portions of the rolls 21 beyond the end of the guide rail 31. As the case is then unrestrained, it is moved by the rotation of the rolls 21 onto the short rolls 22 and then onto the end portions of rolls 23 which form the second leg of the U-flow unit. The case is then brought to a stop against the guide rail 36 which, like rail 31 is low enough to be engaged only by the end wall 12 without being contacted by the lower edge of the released flap 16. This flap will then flare out sufliciently to be engaged by the folding plow to be described presently.

After the case arrives on the live rolls 23 it is then ready to be moved lengthwise of the rolls so that the connecting strip 18 may be severed. For this purpose a pivoted, spring-loaded guide member 37 is mounted on a pivot pin 38 supported on frame member 24 with its free end extended to a point near the ends of the rolls 22 to provide suflicient space for a case of maximum size to pass between such end and the frame member 25. The guide 37 has an arm 39 extended at an angle. A coil spring 40 has one end secured to the arm and the other end of the spring is suitably secured to a fixed frame piece or bracket 41. To limit the swing of the guide member 37 the threaded end of a short rod 42 is received within a threaded opening in the frame member 24. The upper free end of the rod is arranged to receive contact by the arm 39, and, by adjusting the rod, the amount of swing of the free end of the guide member 37 may be fixed as desired.

The outer end of the guide member is flared at 43 in a direction away from the rolls 23. By adjusting the pivoted guide 37 so that the case will first engage the flared end 43 and move the free end slightly against the spring pressure, the case will be held snugly between the pivoted guide 37 and the fixed guide rail 36.

The pivoted guide member 37 is formed so that it will be engaged only by end wall 10 below the lower free edge of the downturned flap 14, thus assuring that the outwardly flaring end of flap 14 will extend over, the guide member.

A strip cutting blade 44 is secured on the straight portion of the pivoted guide member 37, preferably near the point where the flared end 43 meets the straight section of the guide, and aligned with the blade 44 is a folding plow 45 arranged so that the flap 14 will contact the outside edge of the plow. Thus, following the severance of the strip 18, the plow 45 will fold the flap 14 first upward and then down and over the top of the case, as indicated in FIG. 4.

A second plow member 46 is secured on the frame member 27 in position to engage the flap 16 as the case advances along the plow and this will fold the flap 16 upward and then downward over the top of the case, as shown in FIG. 4.

As herein illustrated, the case after moving onto the ends of the rolls 23, is propelled past the blade 44 by a follower plate 47, fixed on the end of a piston rod 48, actuated by a piston movable within cylinder 49. The follower plate remains in retracted position until after the case has moved onto the ends of the live rolls 23, whereupon the plate 47 is advanced to propel the case.

Suitable valve means, not shown, is employed to control the flow of fluid under pressure to the cylinders 35 and 49. The valve means may be actuated manually or by suitable mechanical or electrical devices in manners that are well known.

When the case arrives near the end of the second leg of the U-flow unit the end flaps 14 and 16 will have approached their closed positions and will be brought to a small angle relative to the top of the case. The side flaps 15 and 17 will remain downwardly extended.

As shown in FIGS. 1, 4 and 5, a transversely extending flap-guide member is arranged at the end of the second leg of the unit. This may comprise a thin sheet-metal plate 50 secured on frame supports 51 and disposed at an angle inclined downwardly at the end of the case path on the second leg of the unit. The leading free corners of the flaps 14 and 16 will engage against the under surface of the guide plate 50 while the flaps are still being controlled by the plow members 45 and 46, and the flaps will be swung down through an additional small angle in the final short distance of case travel to bring the free edges of the flaps below the level of the end portions of the plows 45 and 46.

As soon as the case arrives at the end of the second leg of the unit the follower plate will be retracted to a position clear of the case path at the opposite end of the second leg of the unit. The case is then discharged by the action of the live rolls 23 on to the conveyor section 3. As the case advances along the rolls and onto conveyor 3 the corners of the flaps 14 and 16 slide along the surface of the guide plate 50. After passing from contact with the plate 50 the flaps will be engaged beneath a suitable holddown bar, as indicated at 52, which may be inclined downward to swing the flaps substantially to their final closed position and maintain them in such position until the time when the side flaps 15 and 17 are to be swung to closed position and sealed to the underlying end wall flaps.

The mechanism for closing the side wall flaps 15 and 17 and for securing such flaps to the previously folded flaps 14 and 16 forms no part of the invention.

An important-variation from the form of invention illustrated in FIG. 1 is shown in FIG. 3. In this form, instead of cutting the second flap connection while the case is advanced along the second leg of the unit, the second flap connection is cut on the transversely extending portion. The cases are fed singly from conveyor 102 onto live rolls 121, 121. Follower plate 133 is used to propel the case past the cutting blade 132, secured on the guide rail 131 which is supported on the frame member 129, and to deliver the case onto a group of liver rolls 130, 130 which are arranged to extend transversely of the rolls 12.1. The rolls 130 rotate in a direction to continue the advance of the case and urge it against the guide rail 125a on the frame member 125.

A piston operated follower plate 136 is employed to propel the case off the rolls 130, along the guide rail 125a and past the blade 144 to cut the connecting strip 18. The case is moved along the short rolls 122, 122 and onto the long rolls 123 after which the follower plate 136 is moved to its fully retracted position to await delivery of the next case into position to be advanced.

As the case is propelled past the blade 144 it is held firmly against the guide rail 125a by means of aspringloaded member, indicated at 128a, pivotally supported on frame member 128.

After the strip 18 is severed and the case reaches the end of its travel, it will be moved endwise of the live rolls 123 by follower plate 147, operated by piston and cylinder mechanism identical with that for follower plate 47. The case will then be moved between guides 136 and 137 and the flaps 16 and 14 will be folded by plow bars, the ends of which are shown at 146 and 145, respectively. The folding action is the same as the action of the plow bars 46 and 45 in the form illustrated in FIG. 1. The remaining structure may be identical with that shown in FIG. 1.

As disclosed in application Ser. No. 660,665, the flaps which are to pass outside the cutting blades may be drawn outwardly by means such as a vacuum cup mechanism located a short distance ahead of the blade so that the leading, free portion of the flap can be positively deflected outward and held momentarily until the leading edge of the flap passes successfully outside the blade.

In the event that the types of cases to be handled are such that it is desirable to employ vacuum cup devices, the form of unit shown in FIG. 3 is preferable because the vacuum cup for the second strip may be located on a fixed frame member such as frame section 125 rather than on the pivoted member 37 of FIG. 1. Furthermore, the location of the vacuum cup device on the pivoted frame 37 would necessitate not only lengthening the frame 37 but the entire unit would need to be lengthened so that the cup could be spaced ahead of the cutting blade 44 the necessary distance.

If a vacuum cup flap-spreading device is to be used on the transverse section of the U-flow unit, the blade 144 is placed a short distance ahead of the position indicated. In addition, the pivoted guide 128a may be omitted when the vacuum cup deflecting device is employed.

The use of vacuum cup flap-spreading devices is desirable when cases of substandard quality are to be handled, in which some of the flap hinge lines have a low degree of resiliency with the consequence that free edges of the flaps will not normally flare appreciably outward of their supporting walls.

It is contemplated that the U-flow units may be made adaptable to cases of different dimensions, and, to accommodate such cases, the guide rails and flap folding plows may be made with provision for suitable adjustment as broadly disclosed in application Ser. No. 660,- 665.

While the present description sets forth preferred embodiments of the invention, various changes may be made in the mechanism as disclosed without departing from the spirit of the invention, and it is therefore desired that the present embodiments be considered in all respects as illustrative and not restrictive, reference being had to the appended claims rather than to the foregoing description to indicate the scope of the invention.

We claim:

1. A mechanism for severing the holding means between the adjacent edges of the cover flaps of a resilient rectangular case on which the outwardly downturned cover flaps at diagonally opposite vertical corners of an expanded case are held along their meeting edges by short connecting strips so that the vertical connected edges of the cover flaps will be maintained in close relation to the attached respective case side and end walls and the opposite unconnected vertical edges of the flaps will flare somewhat away from their attached walls, such mechanism comprising:

a conveyor system having first and second elongated,

spaced legs and a connecting transverse portion arranged in the form of a U-shaped unit on which a rectangular case as defined may be advanced without change in angular position;

said spaced legs including supporting and conveying means to advance or urge a case in the same direction transversely of the legs;

a first guide member located along the first leg, on the side toward which the conveying means advances a case, to limit the transverse movement of a case thereon, said guide member terminating short of the transverse portion of the U-shaped unit to permit free advance of the case along the transverse portion to the second leg;

a second guide member located transversely along the end of the first leg and extending along the side of the adjacent transverse portion;

a first strip-severing means associated with the first guide member for severing the strip. at one corner of the case;

a second strip-severing means associated with the second guide member for severing the strip at the diagonally opposite corner of the case;

separate means for propelling the case lengthwise of the first leg and past the first severing means to sever the first connecting strip and to deliver the case to the discharge end of the first leg; and

separate means acting thereafter to propel the case laterally of the end of the first leg along the second guide member, past the second severing means, and along the transverse portion of the unit to sever the second connecting strip at the diagonally opposite corner of the case, and to deliver the case at the receiving end of the second leg.

2. The invention defined in claim 1 in which the supporting and conveying means included in the first leg of the unit comprises a plurality of live rolls.

3. The invention defined in claim 1 in which the conveying means included in the second leg of the unit comprises a plurality of live rolls.

4. The invention defined in claim 1 in which the transverse portion of the unit has included therein a plurality of live rolls arranged to convey cases toward the second leg.

5. The invention defined in claim 1 in which the means for propelling the case lengthwise of the first leg comprises a movable follower plate.

6. The invention defined in claim 1 in which the means for propelling the casetlaterally of the first leg and along the transverse portion of the unit comprises a movable follower plate.

7. The invention defined in claim 1 in which the supporting and conveying means included in the second leg of the unit comprises a plurality of live rolls, and a movable follower plate means is provided for propelling a case lengthwise of the second leg of the unit.

8. The invention defined in claim 1 in which means are provided for propelling the case longitudinally of the second leg from its end adjacent the transverse portion to its free end.

9. In a case treating mechanism adapted for operative assembly between the spaced, or interrupted, sections of an existing principal conveyor line,

a conveyor system having two elongated, spaced legs and a connecting, transverse portion, arranged in the form of a U-shaped unit;

each leg of the unit including supporting and conveying means to advance or urge a rectangular case in a direction laterally of the legs and in the same direction;

means for propelling a case along the transverse portion and onto the adjacent end of the second leg;

a first, separate conveying means for propelling a case from the free end of the first leg of the unit to a position aligned with the transverse portion;

a second, separate conveying means for propelling a case from a position on the end of the second leg, adjacent the transverse portion of the unit, to a position adjacent the free end of the second leg;

whereby a rectangular case may be advanced in sequence and without change in angular position,

first, laterally of the first leg at its free end;

then lengthwise of the first leg to its end by said separate conveying means;

then laterally of the first leg onto the transverse portion of the unit;

then onto the adjacent end of the second leg;

then, by the second separate conveying means, to a position adjacent the free end of the second then discharged laterally ofif the free end of the second leg;

a guide member disposed along the first leg to limit the lateral movement of a case thereon, said guide member terminating adjacent the near edge of the transverse portion, whereby a case, being advanced to a location adjacent the transverse portion, may move laterally of the first leg, past the end of the guide member, thence along the transverse portion, and onto the second leg; and

a guide member disposed along the second leg to limit the lateral movement of a case thereon, said guide member terminating short of the free end of the second leg a sufficient distance to permit the case to move past the end of the guide member and to be discharged laterally off the free end of the second leg.

10. A mechanism for severing the holding means between the adjacent edges of the cover flaps of a resilient rectangular case on which the outwardly downturned cover flaps at diagonally opposite vertical corners of an expanded case are held along their meeting edges by short connecting strips so that the vertical connected edges of the cover flaps will be maintained in close relation to the attached respective case side and end walls and the opposite unconnected vertical edges of the flaps will flare somewhat away from their attached walls, such mechanism comprising "a conveyor unit having first and second elongated,

spaced legs and a connecting transverse portion arranged in U-shape on which a rectangular case as defined may be advanced without change in angular position, such unit being adapted for operative as- 8 sembly between the spaced or interrupted sections of an existing principal conveyor line, the case being received laterally onto the free end of the first leg and discharged laterally from the free end of the second leg;

a first strip-severing means operatively associated with the first leg; I,

a second strip-severing means operatively associated with the second leg; I ,1 means for propelling a case, as defined, past the first severing means; a means for propelling such case past the second severing means and to the discharge end of the second oppositely disposed folding plows located at the sides of the second leg in position to fold the opposite, released lateral fiaps upwardly and then downwardly over the case to a position at a small angle above the top of the case; means at the free end of the second leg to move a case, with flaps sofolded, laterally of such second leg and Without change in angular position, whereby said lateral folded flaps become leading and trailing flaps of the case; a

a guide means located adjacent the end of the, second leg and extending transversely thereof for engaging the adjacent free corner of the folded flap that is to become the trailing flap after the case is moved laterally on the second leg, said guide means serving to swing said flap farther downward as the case is completing its travel lengthwise of the second leg, said guide means extending sufficiently in a direction transverse to the second leg to hold the trailing fiap in its then lowered position as the case is advanced along the transverse guide means, whereby the trailing flap is maintained in such lowered position as the case moves laterally of the second legto'a position clear of the folding plow for the opposite flap which has become the leading flap.

11. A mechanism for severing the holding means between the adjacent edges of the cover flaps of a resilient rectangular case on which the outwardly downturned cover flaps at diagonally opposite vertical corners of an expanded case are held along their meeting edges by short connecting strips so that the vertical connected edges of the cover flaps will be maintained in close relation to the attached respective case and end walls, and the opposite, unconnected vertical edges of the fiaps will flare somewhat away from their attached walls, such mechanism comprising v a first connecting-strip severing station including a first support means on which a case of thetype described may be advanced;

a guide member at said station; a first strip severing means associated with the guide member for severing the strip at one corner of the casevas the case is advanced along the guidemember; said support means having a section extended there,-

from beyond the end of the guide member and on which a case may be advanced transversely past the end of the guide member; 1' a second strip severing station including a second support means on which the case may be received from said extended section and advanced in an opposite direction from the travel of a case on the first-sup; port means; a Y V a guide member at the second strip-severing stat-ion, said guide member being generally parallel to the first guide member; and v a second strip severing means associated with the sec-Y ond guide member for severing the strip connecting the flap edges at the corner of the case dia gonally opposite to the first strip as the case is advanced along such guide member. I 1 I I 12. The invention as defined in claim 11 in which the support means, included in the first strip-severing station, comprises a plurality of elongated live rolls disposed generally parallel to the guide member at the first station, said rolls being rotatable in a direction to urge a case thereon against the guide member, and means for propelling the case lengthwise of the rolls and past the strip severing means.

13. The invention defined in claim 11 in which the support means included in the first strip-severing station, comprises a group of live rolls disposed generally parallel to and beyond the end of the guide member, said rolls being rotatable in a direction to urge the case against the guide member, the extended section of said support means also comprising a group of live rolls located beyond the end of the guide member and rotatable to advance the case transversely past the end of the guide member, and a follower plate means for propelling the case past the strip-severing means to a position beyond the guide member, whereby the case will be advanced by the live rolls to the second strip-severing station,

References Cited UNITED STATES PATENTS 632,103 8/1899 Craw 53374 2,643,497 6/1953 Woelfer 53-388X 2,744,373 5/1956 Hull et al 53-374 3,373,543 3/1968 Nigrelli et al. 53--381 

